Hello aspirant,
For Bsc.physics there is no upper age limit so criteria of admission is not different for you due to gap.
Some university gives admission by taking entrance exam and some on merit based.For knowing any any specific college in Gujarat mention that.
B.Sc Physics is an undergraduate program, the minimum eligibility for which is an intermediate 10+2 in Science with Physics, Chemistry, Mathematics/Biology and English as compulsory subjects
Hope it helps.